Effects of various processing methods on the dietary fiber and antioxidant properties of Bignay (Antidesma bunius L. Spreng) fruit

Abstract

Bignay (Antidesma bunius L. Spreng) is an indigenous fruit in the Philippines known for its bioactive compounds and is commonly preserved by conventional freezing. Processing can be done to improve its storage condition and convert it into functional ingredients. This study aimed to determine the effect of freeze-drying, oven drying (50°C), spray drying, and juice concentrating on the dietary fiber composition, phenolic compounds, and antioxidant activity of Bignay. Results showed that oven drying increased the total dietary fiber of Bignay by 29% while freeze drying resulted to an increase in total phenolics, total flavonoids, and total anthocyanin by 69%, 55%, and 66%, respectively, with an increase in antioxidant activity in terms of DPPH, FRAP, and ABTS by 57%, 15% and 31%, respectively. Spray drying was found to be the most detrimental method while juice concentration gave little to no significant effects. Epicatechin, catechin, and gallic acid were the main phenolic compounds quantified in the processed Bignay. The study recommends that freeze-drying is the best method followed by oven drying, concentration, and spray drying.

Keywords

• Bignay
• Fiber content
• Fruit processing
• Phenolic compounds
• Antioxidant activity